What was found
(CAN) PILOT LANDED TO CONDUCT TASK AT WELL SITE. DURING ATTEMPTED START UP, THE AIRCRAFT WOULD NOT START. AFTER A SHORT TIME, THE PILOT ATTEMPTED AGAIN AND THE AIRCRAFT STARTED. IT RAN VERY ROUGH AND EXCESSIVE VIBRATIONS. PILOT TOOK THE ENGINE POWER UP TO CHECK IF THE ISSUE WAS MAGNETO`S. HE THEN SHUT IT DOWN. MAINTENANCE CONDUCTED FURTHER INVESTIGATIONS AND FOUND CYLINDER NR 3 INTAKE VALVE HAD SNAPPED OR FRACTURED IN 3 PIECES. PORTION OF THE VALVE WAS FOUND IN THE INTAKE INDUCTION BOX. WILL NOTIFY WHEN FURTHER DETAILS ARE AVAILABLE. (TC NR 20070518002)